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          <h1 class="post-title" itemprop="name headline">python学习(十一)元类学习和应用</h1>
        

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        <p>最近学习了python的<code>错误处理</code>和几种<code>测试</code>方法</p>
<h2 id="try-except"><a href="#try-except" class="headerlink" title="try except"></a><code>try except</code></h2><p>可以通过<code>try except</code>方式捕捉异常<br><figure class="highlight python"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br><span class="line">9</span><br></pre></td><td class="code"><pre><span class="line"><span class="keyword">try</span>:</span><br><span class="line">    print(<span class="string">'try...'</span>)</span><br><span class="line">    r = <span class="number">10</span>/<span class="number">0</span></span><br><span class="line">    print(<span class="string">'result is :'</span>, r)</span><br><span class="line"><span class="keyword">except</span> ZeroDiversionError <span class="keyword">as</span> e:</span><br><span class="line">    print(<span class="string">'except is :'</span>, e)</span><br><span class="line"><span class="keyword">finally</span>:</span><br><span class="line">    print(<span class="string">'finally ...'</span>)</span><br><span class="line">print(<span class="string">'END'</span>)</span><br></pre></td></tr></table></figure></p>
<p>可以捕捉不同类型的错误，编写多个except<br><a id="more"></a><br><figure class="highlight python"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br><span class="line">9</span><br><span class="line">10</span><br><span class="line">11</span><br></pre></td><td class="code"><pre><span class="line"><span class="keyword">try</span>:</span><br><span class="line">    print(<span class="string">'try...'</span>)</span><br><span class="line">    r = <span class="number">10</span>/int(<span class="string">'a'</span>)</span><br><span class="line">    print(<span class="string">'result is: '</span>, r)</span><br><span class="line"><span class="keyword">except</span> ValueError <span class="keyword">as</span> e:</span><br><span class="line">    print(<span class="string">'ValueError : '</span>, e)</span><br><span class="line"><span class="keyword">except</span> ZeroDiversionError <span class="keyword">as</span> e:</span><br><span class="line">    print(<span class="string">'ZeroDivisionError is : '</span>, e)</span><br><span class="line"><span class="keyword">finally</span>:</span><br><span class="line">    print(<span class="string">'finally ...'</span>)</span><br><span class="line">print(<span class="string">'END'</span>)</span><br></pre></td></tr></table></figure></p>
<p>try except同样支持else结构<br><figure class="highlight python"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br><span class="line">9</span><br><span class="line">10</span><br><span class="line">11</span><br><span class="line">12</span><br><span class="line">13</span><br></pre></td><td class="code"><pre><span class="line"><span class="keyword">try</span>:</span><br><span class="line">    print(<span class="string">'try... '</span>)</span><br><span class="line">    r = <span class="number">10</span>/int(<span class="string">'2'</span>)</span><br><span class="line">    print(<span class="string">'result is : '</span>, r)</span><br><span class="line"><span class="keyword">except</span> ValueError <span class="keyword">as</span> e:</span><br><span class="line">    print(<span class="string">'ValueError : '</span>, e)</span><br><span class="line"><span class="keyword">except</span> ZeroDivisionError <span class="keyword">as</span> e:</span><br><span class="line">    print(<span class="string">'ZeroDivisionError is : '</span>, e)</span><br><span class="line"><span class="keyword">else</span>:</span><br><span class="line">    print(<span class="string">'no error'</span>)</span><br><span class="line"><span class="keyword">finally</span>:</span><br><span class="line">    print(<span class="string">'finally ...'</span>)</span><br><span class="line">print(<span class="string">'END'</span>)</span><br></pre></td></tr></table></figure></p>
<p>某个函数调用出现异常，在上层同样可以捕获到</p>
<figure class="highlight python"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br><span class="line">9</span><br><span class="line">10</span><br><span class="line">11</span><br><span class="line">12</span><br><span class="line">13</span><br></pre></td><td class="code"><pre><span class="line"><span class="function"><span class="keyword">def</span> <span class="title">foo</span><span class="params">(s)</span>:</span></span><br><span class="line">    <span class="keyword">return</span> <span class="number">10</span>/int(s)</span><br><span class="line"><span class="function"><span class="keyword">def</span> <span class="title">bar</span><span class="params">(s)</span>:</span></span><br><span class="line">    <span class="keyword">return</span>  foo(s) * <span class="number">2</span></span><br><span class="line"></span><br><span class="line"><span class="function"><span class="keyword">def</span> <span class="title">main</span><span class="params">()</span>:</span></span><br><span class="line">    <span class="keyword">try</span>:</span><br><span class="line">        bar(<span class="string">'0'</span>)</span><br><span class="line">    <span class="keyword">except</span> Exception <span class="keyword">as</span> e:</span><br><span class="line">        print(<span class="string">'Exception is : '</span>, e)</span><br><span class="line">    <span class="keyword">finally</span>:</span><br><span class="line">        print(<span class="string">'finally...'</span>)</span><br><span class="line">main()</span><br></pre></td></tr></table></figure>
<h2 id="logging"><a href="#logging" class="headerlink" title="logging"></a>logging</h2><p>python 提供打日志方式输出异常，并且不会因为出现异常导致程序中断<br><figure class="highlight python"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br><span class="line">9</span><br><span class="line">10</span><br><span class="line">11</span><br><span class="line">12</span><br><span class="line">13</span><br></pre></td><td class="code"><pre><span class="line"><span class="keyword">import</span> logging</span><br><span class="line"><span class="function"><span class="keyword">def</span> <span class="title">foo</span><span class="params">(s)</span>:</span></span><br><span class="line">    <span class="keyword">return</span> <span class="number">10</span>/int(s)</span><br><span class="line"><span class="function"><span class="keyword">def</span> <span class="title">bar</span><span class="params">(s)</span>:</span></span><br><span class="line">    <span class="keyword">return</span> foo(s) * <span class="number">2</span></span><br><span class="line"></span><br><span class="line"><span class="function"><span class="keyword">def</span> <span class="title">main</span><span class="params">()</span>:</span></span><br><span class="line">    <span class="keyword">try</span>:</span><br><span class="line">        bar(<span class="string">'0'</span>)</span><br><span class="line">    <span class="keyword">except</span> Exception <span class="keyword">as</span> e:</span><br><span class="line">        logging.exception(e)</span><br><span class="line">main()</span><br><span class="line">print(<span class="string">'END'</span>)</span><br></pre></td></tr></table></figure></p>
<p>如果想要将异常处理的更细致，可以自定义一个异常类，继承于几种错误类，如ValueError等，在可能出现问题的地方将错误抛出来<br><figure class="highlight python"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br></pre></td><td class="code"><pre><span class="line"><span class="class"><span class="keyword">class</span> <span class="title">FooError</span><span class="params">(ValueError)</span>:</span></span><br><span class="line">    <span class="keyword">pass</span></span><br><span class="line"><span class="function"><span class="keyword">def</span> <span class="title">foo</span><span class="params">(s)</span>:</span></span><br><span class="line">    n = int(s)</span><br><span class="line">    <span class="keyword">if</span> n == <span class="number">0</span>:</span><br><span class="line">        <span class="keyword">raise</span> FooError(<span class="string">'invalid error is : %s'</span> %s)</span><br><span class="line">    <span class="keyword">return</span> <span class="number">10</span>/n</span><br><span class="line">foo(<span class="string">'0'</span>)</span><br></pre></td></tr></table></figure></p>
<p>错误可以一层一层向上抛，直到有上层能处理这个错误为止<br><figure class="highlight python"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br><span class="line">9</span><br><span class="line">10</span><br><span class="line">11</span><br><span class="line">12</span><br><span class="line">13</span><br><span class="line">14</span><br></pre></td><td class="code"><pre><span class="line"><span class="function"><span class="keyword">def</span> <span class="title">foo</span><span class="params">(s)</span>:</span></span><br><span class="line">    n = int(s)</span><br><span class="line">    <span class="keyword">if</span> n==<span class="number">0</span>:</span><br><span class="line">        <span class="keyword">raise</span> ValueError(<span class="string">'invalid error is: %s'</span> %s)</span><br><span class="line">    <span class="keyword">return</span> <span class="number">10</span>/n</span><br><span class="line"></span><br><span class="line"><span class="function"><span class="keyword">def</span> <span class="title">bar</span><span class="params">()</span>:</span></span><br><span class="line">    <span class="keyword">try</span>:</span><br><span class="line">        foo(<span class="string">'0'</span>)</span><br><span class="line">    <span class="keyword">except</span> ValueError <span class="keyword">as</span> e:</span><br><span class="line">        print(<span class="string">'ValueError'</span>)</span><br><span class="line">        <span class="keyword">raise</span></span><br><span class="line"></span><br><span class="line">bar()</span><br></pre></td></tr></table></figure></p>
<p>logging可以设置不同的级别,通过basicConfig可以设置<br><figure class="highlight python"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br><span class="line">9</span><br><span class="line">10</span><br><span class="line">11</span><br></pre></td><td class="code"><pre><span class="line"><span class="keyword">import</span> logging </span><br><span class="line">logging.basicConfig(level=logging.INFO)</span><br><span class="line"></span><br><span class="line"><span class="function"><span class="keyword">def</span> <span class="title">foo</span><span class="params">(s)</span>:</span></span><br><span class="line">    n = int(s)</span><br><span class="line">    <span class="keyword">return</span> <span class="number">10</span>/n</span><br><span class="line"></span><br><span class="line"><span class="function"><span class="keyword">def</span> <span class="title">main</span><span class="params">()</span>:</span></span><br><span class="line">    m = foo(<span class="string">'0'</span>)</span><br><span class="line">    logging.info(<span class="string">'n is : %d'</span> %m)</span><br><span class="line">main()</span><br></pre></td></tr></table></figure></p>
<h2 id="断言assert"><a href="#断言assert" class="headerlink" title="断言assert"></a>断言assert</h2><p>大部分语言都支持assert，python也一样，在可能出错的地方写assert，会在异常出现时使程序终止<br><figure class="highlight python"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br><span class="line">9</span><br></pre></td><td class="code"><pre><span class="line"><span class="function"><span class="keyword">def</span> <span class="title">foo</span><span class="params">(s)</span>:</span></span><br><span class="line">    n = int(s)</span><br><span class="line">    <span class="keyword">assert</span> n != <span class="number">0</span> ,<span class="string">'n is zero'</span></span><br><span class="line">    <span class="keyword">return</span> <span class="number">10</span>/n</span><br><span class="line"></span><br><span class="line"><span class="function"><span class="keyword">def</span> <span class="title">main</span><span class="params">()</span>:</span></span><br><span class="line">    foo(<span class="string">'0'</span>)</span><br><span class="line"></span><br><span class="line">main()</span><br></pre></td></tr></table></figure></p>
<h2 id="pdb调试和set-trace"><a href="#pdb调试和set-trace" class="headerlink" title="pdb调试和set_trace"></a>pdb调试和set_trace</h2><p>pdb调试用 python -m pdb 文件名.py, 单步执行敲n,退出为q<br>python 可以在代码里设置断点，在程序自动执行到断点位置暂停,暂停在<code>set_trace</code>的代码行<br><figure class="highlight python"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br></pre></td><td class="code"><pre><span class="line"><span class="keyword">import</span> pdb</span><br><span class="line"><span class="function"><span class="keyword">def</span> <span class="title">foo</span><span class="params">(s)</span>:</span></span><br><span class="line">    n = int(s)</span><br><span class="line">    pdb.set_trace()</span><br><span class="line">    <span class="keyword">return</span> <span class="number">10</span>/n</span><br><span class="line"><span class="function"><span class="keyword">def</span> <span class="title">main</span><span class="params">()</span>:</span></span><br><span class="line">    m = foo(<span class="string">'0'</span>)</span><br><span class="line">main()</span><br></pre></td></tr></table></figure></p>
<h2 id="单元测试"><a href="#单元测试" class="headerlink" title="单元测试"></a>单元测试</h2><p>先实现一个自己定义的Dict类，将文件保存为mydict.py<br><figure class="highlight python"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br><span class="line">9</span><br><span class="line">10</span><br></pre></td><td class="code"><pre><span class="line"><span class="class"><span class="keyword">class</span> <span class="title">Dict</span><span class="params">(dict)</span>:</span></span><br><span class="line">    <span class="function"><span class="keyword">def</span> <span class="title">__init__</span><span class="params">(self, **kw)</span>:</span></span><br><span class="line">        super(Dict, self).__init__(**kw)</span><br><span class="line">    <span class="function"><span class="keyword">def</span> <span class="title">__getattr__</span><span class="params">(self, key)</span>:</span></span><br><span class="line">        <span class="keyword">try</span>:</span><br><span class="line">            <span class="keyword">return</span> self[key]</span><br><span class="line">        <span class="keyword">except</span> Exception <span class="keyword">as</span> e:</span><br><span class="line">            <span class="keyword">raise</span> AttributeError(<span class="string">'AttributeError is :%s'</span>, e)</span><br><span class="line">    <span class="function"><span class="keyword">def</span> <span class="title">__setattr__</span><span class="params">(self, key, value)</span>:</span></span><br><span class="line">        self[key] =  value</span><br></pre></td></tr></table></figure></p>
<p>python 提供了单元测试的类，开发者可以继承<code>unittest.Test</code>实现特定的测试类,下面实现Dict的单元测试类，保存为<code>unittestdict.py</code><br><figure class="highlight python"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br><span class="line">9</span><br><span class="line">10</span><br><span class="line">11</span><br><span class="line">12</span><br><span class="line">13</span><br><span class="line">14</span><br><span class="line">15</span><br><span class="line">16</span><br><span class="line">17</span><br><span class="line">18</span><br><span class="line">19</span><br><span class="line">20</span><br><span class="line">21</span><br><span class="line">22</span><br><span class="line">23</span><br><span class="line">24</span><br><span class="line">25</span><br><span class="line">26</span><br><span class="line">27</span><br><span class="line">28</span><br><span class="line">29</span><br><span class="line">30</span><br><span class="line">31</span><br><span class="line">32</span><br><span class="line">33</span><br><span class="line">34</span><br><span class="line">35</span><br><span class="line">36</span><br><span class="line">37</span><br><span class="line">38</span><br></pre></td><td class="code"><pre><span class="line"><span class="keyword">import</span> unittest</span><br><span class="line"><span class="keyword">from</span> mydict <span class="keyword">import</span> Dict</span><br><span class="line"></span><br><span class="line"><span class="class"><span class="keyword">class</span> <span class="title">TestDict</span><span class="params">(unittest.TestCase)</span>:</span></span><br><span class="line">	<span class="function"><span class="keyword">def</span> <span class="title">setUp</span><span class="params">(self)</span>:</span></span><br><span class="line">		print(<span class="string">'setUp...'</span>)</span><br><span class="line">	<span class="function"><span class="keyword">def</span> <span class="title">tearDown</span><span class="params">(self)</span>:</span></span><br><span class="line">		print(<span class="string">'tear Down...'</span>)</span><br><span class="line"></span><br><span class="line">	<span class="function"><span class="keyword">def</span> <span class="title">test_init</span><span class="params">(self)</span>:</span></span><br><span class="line">		d = Dict(a=<span class="string">'testa'</span>, b = <span class="number">1</span>)</span><br><span class="line">		self.assertEqual(d.a, <span class="string">'testa'</span>)</span><br><span class="line">		self.assertEqual(d.b, <span class="number">1</span>)</span><br><span class="line">		self.assertTrue(isinstance(d, dict))</span><br><span class="line"></span><br><span class="line">	<span class="function"><span class="keyword">def</span> <span class="title">test_key</span><span class="params">(self)</span>:</span></span><br><span class="line">		d = Dict()</span><br><span class="line">		d[<span class="string">'name'</span>] = <span class="string">'hmm'</span></span><br><span class="line">		self.assertEqual(d.name, <span class="string">'hmm'</span>)</span><br><span class="line"></span><br><span class="line">	<span class="function"><span class="keyword">def</span> <span class="title">test_attr</span><span class="params">(self)</span>:</span></span><br><span class="line">		d = Dict()</span><br><span class="line">		d.name = <span class="string">'hmm'</span></span><br><span class="line">		self.assertEqual(d[<span class="string">'name'</span>], <span class="string">'hmm'</span>)</span><br><span class="line">		self.assertTrue(<span class="string">'name'</span> <span class="keyword">in</span> d)</span><br><span class="line"></span><br><span class="line">	<span class="function"><span class="keyword">def</span> <span class="title">test_attrerror</span><span class="params">(self)</span>:</span></span><br><span class="line">		d = Dict()</span><br><span class="line">		<span class="keyword">with</span> self.assertRaises(AttributeError):</span><br><span class="line">			value = d.empty</span><br><span class="line">	</span><br><span class="line">	<span class="function"><span class="keyword">def</span> <span class="title">test_keyerror</span><span class="params">(self)</span>:</span></span><br><span class="line">		d = Dict()</span><br><span class="line">		<span class="keyword">with</span> self.assertRaises(AttributeError):</span><br><span class="line">			value = d[<span class="string">'empty'</span>]</span><br><span class="line">	</span><br><span class="line"><span class="keyword">if</span> __name__ == <span class="string">'__main__'</span>:</span><br><span class="line">	unittest.main()</span><br></pre></td></tr></table></figure></p>
<p>运行unittest.py可以检测mydict中Dict类是否有错误</p>
<h2 id="文档测试"><a href="#文档测试" class="headerlink" title="文档测试"></a><code>文档测试</code></h2><p>文档测试在代码中按照特定格式编写python输入和期待的输出，通过python提供的文档测试类，实现测试代码的目的<br><figure class="highlight python"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br><span class="line">9</span><br><span class="line">10</span><br><span class="line">11</span><br><span class="line">12</span><br><span class="line">13</span><br><span class="line">14</span><br><span class="line">15</span><br><span class="line">16</span><br><span class="line">17</span><br><span class="line">18</span><br><span class="line">19</span><br><span class="line">20</span><br><span class="line">21</span><br><span class="line">22</span><br><span class="line">23</span><br><span class="line">24</span><br><span class="line">25</span><br><span class="line">26</span><br><span class="line">27</span><br><span class="line">28</span><br></pre></td><td class="code"><pre><span class="line"><span class="class"><span class="keyword">class</span> <span class="title">Dict</span><span class="params">(dict)</span>:</span></span><br><span class="line">	<span class="string">'''</span></span><br><span class="line"><span class="string">	&gt;&gt;&gt; d1 = Dict()</span></span><br><span class="line"><span class="string">	&gt;&gt;&gt; d1['x'] = 100</span></span><br><span class="line"><span class="string">	&gt;&gt;&gt; d1.x</span></span><br><span class="line"><span class="string">	100</span></span><br><span class="line"><span class="string">	&gt;&gt;&gt; d1.y = 200</span></span><br><span class="line"><span class="string">	&gt;&gt;&gt; d1['y']</span></span><br><span class="line"><span class="string">	200</span></span><br><span class="line"><span class="string">	&gt;&gt;&gt; d2=Dict(a=1,b=2,c='m')</span></span><br><span class="line"><span class="string">	&gt;&gt;&gt; d2.c</span></span><br><span class="line"><span class="string">	'm'</span></span><br><span class="line"><span class="string">	</span></span><br><span class="line"><span class="string">	'''</span></span><br><span class="line">	<span class="function"><span class="keyword">def</span> <span class="title">__init__</span><span class="params">(self, **kw)</span>:</span></span><br><span class="line">		super(Dict,self).__init__(**kw)</span><br><span class="line">	<span class="function"><span class="keyword">def</span> <span class="title">__getattr__</span><span class="params">(self,key)</span>:</span></span><br><span class="line">		<span class="keyword">try</span>:</span><br><span class="line">			<span class="keyword">return</span> self[key]</span><br><span class="line">		<span class="keyword">except</span> KeyError:</span><br><span class="line">			<span class="keyword">raise</span> AttributeError(<span class="string">'AttributeError key is %s'</span> %key)</span><br><span class="line">	<span class="function"><span class="keyword">def</span> <span class="title">__setattr__</span><span class="params">(self,key,value)</span>:</span></span><br><span class="line">		self[key] = value</span><br><span class="line"></span><br><span class="line"></span><br><span class="line"><span class="keyword">if</span> __name__ == <span class="string">'__main__'</span>:</span><br><span class="line">	<span class="keyword">import</span> doctest</span><br><span class="line">	doctest.testmod()</span><br></pre></td></tr></table></figure></p>

      
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        .append('<div class="search-popup-overlay local-search-pop-overlay">' +
          '<div id="search-loading-icon">' +
          '<i class="fa fa-spinner fa-pulse fa-5x fa-fw"></i>' +
          '</div>' +
          '</div>')
        .css('overflow', 'hidden');
      $("#search-loading-icon").css('margin', '20% auto 0 auto').css('text-align', 'center');

      $.ajax({
        url: path,
        dataType: isXml ? "xml" : "json",
        async: true,
        success: function(res) {
          // get the contents from search data
          isfetched = true;
          $('.popup').detach().appendTo('.header-inner');
          var datas = isXml ? $("entry", res).map(function() {
            return {
              title: $("title", this).text(),
              content: $("content",this).text(),
              url: $("url" , this).text()
            };
          }).get() : res;
          var input = document.getElementById(search_id);
          var resultContent = document.getElementById(content_id);
          var inputEventFunction = function() {
            var searchText = input.value.trim().toLowerCase();
            var keywords = searchText.split(/[\s\-]+/);
            if (keywords.length > 1) {
              keywords.push(searchText);
            }
            var resultItems = [];
            if (searchText.length > 0) {
              // perform local searching
              datas.forEach(function(data) {
                var isMatch = false;
                var hitCount = 0;
                var searchTextCount = 0;
                var title = data.title.trim();
                var titleInLowerCase = title.toLowerCase();
                var content = data.content.trim().replace(/<[^>]+>/g,"");
                var contentInLowerCase = content.toLowerCase();
                var articleUrl = decodeURIComponent(data.url);
                var indexOfTitle = [];
                var indexOfContent = [];
                // only match articles with not empty titles
                if(title != '') {
                  keywords.forEach(function(keyword) {
                    function getIndexByWord(word, text, caseSensitive) {
                      var wordLen = word.length;
                      if (wordLen === 0) {
                        return [];
                      }
                      var startPosition = 0, position = [], index = [];
                      if (!caseSensitive) {
                        text = text.toLowerCase();
                        word = word.toLowerCase();
                      }
                      while ((position = text.indexOf(word, startPosition)) > -1) {
                        index.push({position: position, word: word});
                        startPosition = position + wordLen;
                      }
                      return index;
                    }

                    indexOfTitle = indexOfTitle.concat(getIndexByWord(keyword, titleInLowerCase, false));
                    indexOfContent = indexOfContent.concat(getIndexByWord(keyword, contentInLowerCase, false));
                  });
                  if (indexOfTitle.length > 0 || indexOfContent.length > 0) {
                    isMatch = true;
                    hitCount = indexOfTitle.length + indexOfContent.length;
                  }
                }

                // show search results

                if (isMatch) {
                  // sort index by position of keyword

                  [indexOfTitle, indexOfContent].forEach(function (index) {
                    index.sort(function (itemLeft, itemRight) {
                      if (itemRight.position !== itemLeft.position) {
                        return itemRight.position - itemLeft.position;
                      } else {
                        return itemLeft.word.length - itemRight.word.length;
                      }
                    });
                  });

                  // merge hits into slices

                  function mergeIntoSlice(text, start, end, index) {
                    var item = index[index.length - 1];
                    var position = item.position;
                    var word = item.word;
                    var hits = [];
                    var searchTextCountInSlice = 0;
                    while (position + word.length <= end && index.length != 0) {
                      if (word === searchText) {
                        searchTextCountInSlice++;
                      }
                      hits.push({position: position, length: word.length});
                      var wordEnd = position + word.length;

                      // move to next position of hit

                      index.pop();
                      while (index.length != 0) {
                        item = index[index.length - 1];
                        position = item.position;
                        word = item.word;
                        if (wordEnd > position) {
                          index.pop();
                        } else {
                          break;
                        }
                      }
                    }
                    searchTextCount += searchTextCountInSlice;
                    return {
                      hits: hits,
                      start: start,
                      end: end,
                      searchTextCount: searchTextCountInSlice
                    };
                  }

                  var slicesOfTitle = [];
                  if (indexOfTitle.length != 0) {
                    slicesOfTitle.push(mergeIntoSlice(title, 0, title.length, indexOfTitle));
                  }

                  var slicesOfContent = [];
                  while (indexOfContent.length != 0) {
                    var item = indexOfContent[indexOfContent.length - 1];
                    var position = item.position;
                    var word = item.word;
                    // cut out 100 characters
                    var start = position - 20;
                    var end = position + 80;
                    if(start < 0){
                      start = 0;
                    }
                    if (end < position + word.length) {
                      end = position + word.length;
                    }
                    if(end > content.length){
                      end = content.length;
                    }
                    slicesOfContent.push(mergeIntoSlice(content, start, end, indexOfContent));
                  }

                  // sort slices in content by search text's count and hits' count

                  slicesOfContent.sort(function (sliceLeft, sliceRight) {
                    if (sliceLeft.searchTextCount !== sliceRight.searchTextCount) {
                      return sliceRight.searchTextCount - sliceLeft.searchTextCount;
                    } else if (sliceLeft.hits.length !== sliceRight.hits.length) {
                      return sliceRight.hits.length - sliceLeft.hits.length;
                    } else {
                      return sliceLeft.start - sliceRight.start;
                    }
                  });

                  // select top N slices in content

                  var upperBound = parseInt('1');
                  if (upperBound >= 0) {
                    slicesOfContent = slicesOfContent.slice(0, upperBound);
                  }

                  // highlight title and content

                  function highlightKeyword(text, slice) {
                    var result = '';
                    var prevEnd = slice.start;
                    slice.hits.forEach(function (hit) {
                      result += text.substring(prevEnd, hit.position);
                      var end = hit.position + hit.length;
                      result += '<b class="search-keyword">' + text.substring(hit.position, end) + '</b>';
                      prevEnd = end;
                    });
                    result += text.substring(prevEnd, slice.end);
                    return result;
                  }

                  var resultItem = '';

                  if (slicesOfTitle.length != 0) {
                    resultItem += "<li><a href='" + articleUrl + "' class='search-result-title'>" + highlightKeyword(title, slicesOfTitle[0]) + "</a>";
                  } else {
                    resultItem += "<li><a href='" + articleUrl + "' class='search-result-title'>" + title + "</a>";
                  }

                  slicesOfContent.forEach(function (slice) {
                    resultItem += "<a href='" + articleUrl + "'>" +
                      "<p class=\"search-result\">" + highlightKeyword(content, slice) +
                      "...</p>" + "</a>";
                  });

                  resultItem += "</li>";
                  resultItems.push({
                    item: resultItem,
                    searchTextCount: searchTextCount,
                    hitCount: hitCount,
                    id: resultItems.length
                  });
                }
              })
            };
            if (keywords.length === 1 && keywords[0] === "") {
              resultContent.innerHTML = '<div id="no-result"><i class="fa fa-search fa-5x" /></div>'
            } else if (resultItems.length === 0) {
              resultContent.innerHTML = '<div id="no-result"><i class="fa fa-frown-o fa-5x" /></div>'
            } else {
              resultItems.sort(function (resultLeft, resultRight) {
                if (resultLeft.searchTextCount !== resultRight.searchTextCount) {
                  return resultRight.searchTextCount - resultLeft.searchTextCount;
                } else if (resultLeft.hitCount !== resultRight.hitCount) {
                  return resultRight.hitCount - resultLeft.hitCount;
                } else {
                  return resultRight.id - resultLeft.id;
                }
              });
              var searchResultList = '<ul class=\"search-result-list\">';
              resultItems.forEach(function (result) {
                searchResultList += result.item;
              })
              searchResultList += "</ul>";
              resultContent.innerHTML = searchResultList;
            }
          }

          if ('auto' === 'auto') {
            input.addEventListener('input', inputEventFunction);
          } else {
            $('.search-icon').click(inputEventFunction);
            input.addEventListener('keypress', function (event) {
              if (event.keyCode === 13) {
                inputEventFunction();
              }
            });
          }

          // remove loading animation
          $(".local-search-pop-overlay").remove();
          $('body').css('overflow', '');

          proceedsearch();
        }
      });
    }

    // handle and trigger popup window;
    $('.popup-trigger').click(function(e) {
      e.stopPropagation();
      if (isfetched === false) {
        searchFunc(path, 'local-search-input', 'local-search-result');
      } else {
        proceedsearch();
      };
    });

    $('.popup-btn-close').click(onPopupClose);
    $('.popup').click(function(e){
      e.stopPropagation();
    });
    $(document).on('keyup', function (event) {
      var shouldDismissSearchPopup = event.which === 27 &&
        $('.search-popup').is(':visible');
      if (shouldDismissSearchPopup) {
        onPopupClose();
      }
    });
  </script>





  

  

  

  
  

  

  

  

</body>
</html>
